Addition of BaTiO3 and carbon nanoparticles to silica aerogel and its dielectric properties

Abstract

A tetramethylorthosilicate(TMOS)/ethanol solution was gelled together with BaTiO3 nanoparticles or carbon nanoparticles. The wet gel was dried in supercritical carbon dioxide, resulting in aerogel nanocomposites with compositions in the range of BaTiO3/ SiO2 = 1/100 to 20/100 and C/SiO2 = 20/100 to 80/100. The bulk density of the aerogel obtained was in the range of 0.1 to 0.2 g/cm3, the porosity was about 95%, and the specific surface area was in the range of 400 to 700m2/g. These values represent the characteristics of the aerogel. The relative permittivity and dielectric loss were respectively approximately 2 and 5 × 10-3 for the BaTiO3-silica aerogel nanocomposite, and in the range of 5 to 10 and 0.012 to 0.4 for the carbon-silica aerogel nanocomposite.